Ask HN: Why are promotion “procedures” uncommon?

Why do so few companies have procedures for leveling up more junior developers? I've noticed that quite often junior devs are very productive, but will operate in a limited scope, without much concern for the big picture, and sometimes struggle to build skills that would allow them to qualify for a more senior role.

When I was a junior dev I found this frustrating because there was an expectation to "act senior" before actually having that authority. Additionally, there was an unspoken expectation that you had to ask for it, which seems to just go against the (inaccurate) belief that so many in this field have that it's a meritocratic.

This seems especially disadvantageous for anyone who feels less comfortable in their role/standing and is less assertive for this or other reasons. I could imagine this is an even bigger problem for people who are different from the current makeup of the team/org, especially for people who are from under-represented groups.

What is your procedure for this as a manager or employee? Is there something I'm missing?